William Thomson Hay was an English comedian who wrote and acted in a schoolmaster sketch that later transferred to the screen, where he also played other authority figures with comic failings. His film Oh, Mr. Porter! (1937), made by Gainsborough Pictures, is often cited as the supreme British-produced film-comedy, and in 1938 he was the third highest-grossing star in the UK. Many comedians have acknowledged him as a major influence. Hay was also a keen amateur astronomer.

Oh, Mr Porter! is a 1937 British comedy film starring Will Hay with Moore Marriott and Graham Moffatt and directed by Marcel Varnel. While not Hay's commercially most successful, it is probably his best-known film to modern audiences. It is widely acclaimed as the best of Hay's work, and a classic of its genre. The film had its first public showing in November 1937 and went on general release on 3 January 1938. The plot of Oh, Mr Porter was loosely based on the Arnold Ridley play The Ghost Train. The title was taken from Oh! Mr Porter, a music hall song.